Artificial teeth.



110.787,352. PATBNTED APR. 18, 1905. C. T. CAMPBELL.

ARTIFICIAL TEETH.

APPLIUATION FILED MAR. 28, 1904.

Z/mssm L @W- m ,ffy 5.

UNTTED STATES Patented April 18, 1905.

COLIN THOMAS AM PBELL, (Y) F l( EN'LVILL E, (JA NA DA.

ARTlFlClAL TEETH.

SPECIFICATION formingpart of Letters Patent No. 787,352, dated April 18, 1905.

Application filed March 23,1904. Serial No. 200,467.

To r/,// 117mm/ 1'/ lil/r/vl/ concer/t:

Be it ltnowu that l, CoLIN 'lnouas GnunicLL. dentist, ot the town ot' lientville, in the county ot Kings and Province ot Nova Scotia, (`anada, have invented certain new and useful lniproveinents iu Vulcanitc Teeth; and l do hereby declare that the following a full, clear. and exact description ot' the same.

A\ly invention relates to improvements in vulcanite teeth in which a cavity-tooth operates in conjunction with a removable U-shaped metal spring-pin: and the objects otl my invention are, tirst, to etlect a strong and sccure attachment ot' the tooth tothe plate, and, second, to lessen the chances ol cracks in the tooth caused by the insertion ot the pin.

l attain the objects ot' my invention by the mechanism illustrated in the drawings tiled herein on the 28th dayotl March, 1901i, Serial No. ZlNLllST, in which- Figure l is a cross-section ot' the entire tooth, showing one-halt ot' the pin in place and one-halt' the concave surface or cavity in the tooth and one-haltI ot a projection in the cavity. Fig. 2 a cross-section otl the entirey tooth with the pin removed and showing one-hall" ot the groove in which the pin rests and one-halt ot' the concave surface or cavity in the tooth and one-halt' of a projection in the cavity. Fig. I is an elevation of the cntire pin. Fig. JL is a plan ot' the tooth with the pin inserted and showing the relative position ot' all the parts, and Fig. 5 is a general view ot' the tooth with the pin removed.

Similar lett-ers reter to similar parts throughout the several views.

A is the pin. B is a projection in the cavity ll. C is an aperture opening into the cavity l?. l@ is the central cavity, and F is the thick part ot' the tooth. The broken line through the center ot lfigs. l and 5 indicate the plane upon which the sectional views are taken.

The pin A is made of tempered metal and is plated to prevent corrosion and when separated from the tooth the ends spring slightly away troni the parallel position, as shown in Fig. i3.

',lhe cavity E is circular in shape and cxl) is a groove in which the pin rests.

l tends from the base ol the. tooth downward.

as shown in Figs. 1, L), and

The aperture (I extends from the palatal or lingual surface ot' the tooth and opens into thc cavity 1C, as shown iu Fig. 5.

The groove l) extends obliquely across the tooth and around the walls or sides ot' the aperture (j and cavity IC, as shown in Fig. Q.

The projection B into cavity E is quartermoon in shape and is placed just above the groove l), as shown in Figs. l, Q, l, and

ln order to place the pin in the tooth, the terminal points ot' the pin are bent till they converge, and then the pin may be slid into the groove l), when the ends ot' the piu will when released spring apart and press against the walls ot' the groove l).

XVhcn the pin is in place, its ends project from the tooth, as in the ordinary pin-tooth, as shown in Figs. l and 1t. The pin when placed in the tooth [ills up that portion ot the groove D which circles cavity IC and slightly projects into cavity 1C, but does not quite [ill the remaining portion ol groove I), which is made in the walls ot aperture (o), as shown in Fig. l. The circular portion ot' the piu rests in that portion otl groove l) which circles cavity E, and the arms ot the pin rest in that portion ot groove l) which is made in the walls or sides ot' aperture C.

The cavity E and aperture (j are when the tooth is set in the plate entirely lilled with the vulcanized rubber ot the plate, and the portions ot' the pin which project troni the tooth are surrounded with thc vulcanized rubber of the plate.

The projection of pin A into cavity E and the projection B holds the rubber otl the plate lirmly in the tooth on account ot' the rubber hardening under and around these projections and preventing it trom moving in any direction.

The pin is held lirmly in place by its own pressure against the walls ot' groove l) and by the vulcanized rubber of the plate, which lills the interior ot' the tooth and surroinuls those portions ot' the pin which project into cavity E. The tooth therefore fastened to the plate by the vulcanized rubber ot' the plate,

portions ot' which enter and Jfill the cavities of the tooth and surround the portions ot' the pin which project from the tooth, thus effecting a strong and secure attachment of the tooth to the plate, and as the pin is not fused in the tooth there is lessened the chances of cracks in the tooth caused by the insertion of the pin. A

I am aware that diatoric teeth having different-shaped cavities and pin-teeth in which the pin is inseparable from the tooth have been used separately prior to my invention; but I am not aware that any tooth combining the two features has ever been used or patented.

What I claim as my invention, and desire to secure by Letters Patent, is-

The combination, in vulcanite teeth, of a tooth having a perpendicular, circular, central cavity extending from the base of the tooth downward into the tooth, and an aperture extending at right angles from the centrai cavity outward to the palatal or lingual 

